Problem: What do the following two equations represent? $2x-y = 4$ $-6x+3y = -12$
Solution: Putting the first equation in $y = mx + b$ form gives: $2x-y = 4$ $-y = -2x+4$ $y = 2x - 4$ Putting the second equation in $y = mx + b$ form gives: $-6x+3y = -12$ $3y = 6x-12$ $y = 2x - 4$ The above equations turn into the same equation, so they represent equal lines.